Flexible cams

ABSTRACT

A means for correcting the contour of a cam partially or throughout its entire periphery without the labor of reshaping or even discarding the original cam. The means consists of a flexible band of steel which is adjustably attached at predetermined points to the side of the original cam. The band is then adjusted radially to the desired contour by set screws at the aforesaid points to obtain the contour correction. The cam follower will then ride on the adjusted flexible cam instead of the original one.

United StatesPatent Bush [54] FLEXIBLE CAMS Inventor: Clarence C. Bush, Belair City, Md.

Assignee: The United States of America as represented by the Secretary of the Army Filed: June 7, 1971 Appl. No.: 147,091

[52] US. Cl ..74/568 FS [58] Field of Search....74/568 FS, 568 M, 568 T, 568

References Cited UNITED STATES PATENTS 2/1958 Skwarek ..74/568 R Int. Cl. ..F16h 54/04 7 51 Aug. 1,1972

2,945,397 7/1960 Caler et al. ..74/568 FS Primary Examiner-William F. ODea Assistant Examiner-F. D. Shoemaker Attorney-Harry M. Saragovitz, Edward J. Kelly and Herbert Berl [5 7] ABSTRACT A means for correcting the contour of a cam partially or throughout its entire periphery without the labor of reshaping or even discarding the original cam. The means consists of a flexible band of steel which is adjustably attached at predetermined points to the side of the original cam. The band is then adjusted radially to the desired contour by set screws at the aforesaid points to obtain the contour correction. The cam follower will then ride on the adjusted flexible cam instead of the original one.

8 Claims, 4 Drawing Figures PATENTEBAUG 1 m2 NVENTOR uyarerzcg cf Bush 6% ATTORNEY3 FLEXIBLE CAMS The invention described herein may be manufactured, used, and licensed by or for the Government for governmental purposes without the payment to me of any royalty thereon.

SUMMARY Corrections to be made in the contours of a quantity of large cams were usually by fill-file and/or grind method, which method was not only slow and laborous, but also highly uneconomical. Sometimes the entire cam, or cams, had to be discarded if it was impossible to make a correction. The method of reshaping required adding of shims or filing down in places along the cams contour. One such example, is the cam used to control the electrically or hydraulically controlled jack used in wind tunnels or petroleum piping. The present invention has for its principal object to eliminate the aforesaid disadvantages by providing a flexible band of steel which is attached to the side of an original cam at predetermined points. At each point, set screws are provided so that the flexible band can be adjusted to provide the correction desired. The cam follower is shifted to ride on the flexible band instead of the original cam. The flexible band may be only one segment of the cam or yet the entire length of the cam surface.

DRAWING DESCRIPTION F IG. 1 is a side view of a cam with the flexible cam of this invention applied thereto;

FIG. 2 is a sectional detail view taken along line 2-2 of FIG. 1;

FIG. 3 is a greatly enlarged detail view of one of the adjusting means, and,

FIG. 4 is a detail view looking in the direction of the arrows 4-4 of FIG. 3.

DETAILED DESCRIPTION Referring in detail to the drawing and in particular to FIG. 1, reference character 1 represents a cam, to be referred to as the original cam throughout this specification. The flexible cam assembly is designated generally by 2. Cam 1 is mounted on a shaft 3 and may be of any shape, it being shown by way of example only. A cam follower is indicated by 4. Flexible cam assembly 2 consists of a flexible band 5 of a material such as steel. Only a portion of 5 is illustrated since the flexible cam may be only a segment or yet extend completely around cam 1. In FIG. 1, band 5 is secured at two points only to original cam 1. Lugs 6 are attached at the aforesaid points by bolts 7, as shown. Band 5 is provided with recessed, elongated slots 8 to provide for movement of band 5 during adjustment and to allow for an unbroken cam surface for cam follower 4 to ride on. An adjusting screw 9 is secured in a smooth bore 10 in each lug 6 and held therein by lock nuts 11a and 11b. Each screw 9 is provided with a head 12 riding in slot 8. Another lock nut 1 1c is provided to hold head 12 fast in slot 8. Head 12 may for example be of the Allen head type having a recessed tool engaging means 13, see FIG. 4. To prevent sideway play of band 5, a keeper 14 may be placed at intervals between lugs 6 and secured to the side of original cam 1 by machine screws 15. Band 5 may be provided with as many elongated slots 8 as are necessary. Lugs 6 will be placed at the points needed for adjustment of the band 5.

OPEMTION The operation of the flexible cam 2 is relatively simple. A segment, or segments of band 5 will be mounted to the side of original cam 1 as desired at points needed for the correction of the cam contour. At least two adjustment points will be required for each segment of band 5. Longer band 5 segments of course, will require more mounting points. Lateral adjustment of band 5 is accomplished by loosening lock nut 11c. Once adjusted nut 11a is then tightened. For radial adjustment of band 5, nuts 11a and 11b are manipulated, the nuts being turned down to move band 5 outward, and upward to move band 5 inward.

When the flexible cam assembly is used for small cams, band 5 may bemade of spring steel.

The amount of radial movement of cam band 5 obviously is determined by the length of adjusting screws 9 and the spacing of lugs 6 from the periphery of original cam 1.

What is claimed is:

1. A flexible cam for compensating for inaccuracies in the cam surface of an original cam comprising a flexible band of material, there being at least two elongated and recessed slots disposed in spaced relation therethrough, at least two mounting members adapted to be mounted in spaced relation to the side of said original cam, means mounted in each said last named members and said flexible band adapted to radially adjust said band relative to said original cam surface, and retention means adapted to be mounted on the side of said original cam between said adjusting means to prevent sideway movement of said band.

2. A device as set forth in claim 1 wherein said flexible band is of a material capable of being bent into a predetermined shape along a portion of or the entire contour of said original cam surface.

3. A device as set forth in claim 2 wherein said flexible member is made of steel.

4. A device as claimed in claim 1 wherein each said member for mounting said flexible band to the side of said original cam is a lug fixed to the side thereof and at predetermined points thereon.

5. A device as claimed in claim 1 wherein means carried by each said mounting member for adjusting said flexible band comprises a set screw mounted for radial movement, said set screw extending through said elongated slots in said band and a plurality of adjusting nuts adapted to regulate and lock said set screw when said band has been adjusted to a predetermined contour.

6. A device as claimed in claim 1 wherein said means for preventing sideway movement of said strip comprises an angle shaped member adapted to receive said strip slidably therein and fixed to the side face of said original cam between said adjusting means.

7. A device as claimed in claim 1 wherein said flexible band is of spring steel.

8. In combination with an original cam member including a cam surface thereon, a flexible cam member for providing a substitute cam surface to compensate for inaccuracies in said original cam surface and adapted to be adjustable in a radial manner to the side of said original cam member, at least two mounting for said inaccuracies in said original cam surface and means mounted on the side of said original cam to prevent sideway movement of said flexible cam member. 

1. A flexible cam for compensating for inaccuracies in the cam surface of an original cam comprising a flexible band of material, there being at least two elongated and recessed slots disposed in spaced relation therethrough, at least two mounting members adapted to be mounted in spaced relation to the side of said original cam, means mounted in each said last named members and said flexible band adapted to radially adjust said band relative to said original cam surface, and retention means adapted to be mounted on the side of said original cam between said adjusting means to prevent sideway movement of said band.
 2. A device as set forth in claim 1 wherein said flexible band is of a material capable of being bent into a predetermined shape along a portion of or the entire contour of said original cam surface.
 3. A device as set forth in claim 2 wherein said flexible member is made of steel.
 4. A device as claimed in claim 1 wherein each said member for mounting said flexible band to the side of said original cam is a lug fixed to the side thereof and at predetermined points thereon.
 5. A device as claimed in claim 1 wherein means carried by each said mounting member for adjusting said flexible band comprises a set screw mounted for radial movement, said set screw extending through said elongated slots in said band and a plurality of adjusting nuts adapted to regulate and lock said set screw when said band has been adjusted to a predetermined contour.
 6. A device as claimed in claim 1 wherein said means for preventing sideway movement of said strip comprises an angle shaped member adapted to receive said strip slidably therein and fixed to the side face of said original cam between said adjusting means.
 7. A device as claimed in claim 1 wherein said flexible band is of spring steel.
 8. In combination with an original cam member including a cam surface thereon, a flexible cam member for providing a substitute cam surface to compensate for inaccuracies in said original cam surface and adapted to be adjustable in a radial manner to the side of said original cam member, at least two mounting members attached at predetermined points to the side of said original cam member, adjusting means carried by said mounting members, one each, and connected to said flexible cam member adapted to move said flexible cam member into positions necessary for compensating for said inaccuracies in said original cam surface and means mounted on the side of said original cam to prevent sideway movement of said flexible cam member. 